"One of our mainstays Du Plessis has injured his finger during the course of the last match and has returned to South Africa for further treatment. We wish him speedy recovery," coach Stephen Fleming said in a statement here.

Usman Khawaja. Pic/ AFP

"We are glad to have roped in Usman Khawaja in the team. His presence will definitely be an advantage to the team and could be pivotal in bolstering the position of the side in the tournament," he added.

Khawaja, who also opens for Australia, has been in great form in the T20 format with his exploits in the Big Bash League.

He was also the leading run-scorer for Australia in the recently-concluded World T20, averaging 35.75 with a top score of 58.

"His imperious form for the Sydney Thunders in the Big Bash League victory last season and being the leading run-scorer for Australia, for the recently-concluded World T20, has made us sit up and notice. His style of play is perfect for the T20 format," Fleming said.